For now, the newest additions (Death Omen, Jugger, Behometh) seem to be concentrated along the edge of the map. I've been sighting Death Omens and Juggernaughts behind Perdida all day. Still have not run across a Behometh.
As for a permenent map? Not gonna happen. Seems every time there is a game update, the ship spawn spots change, too. Guess that's to keep us on our toes